The invention relates to a filter press whose filter plates and end plate are centrally suspended at the lower, for example, inner flanges, by two parallel double T-shaped guide members supported by support pillars by two rollers mounted opposite a plane of the filter plate and staggered alternately in opposite directions, on a yoke piece fastened to the top of the filter plates, and which is equipped with a guide device to prevent the filter plate from swinging.
In, for example, German Pat. No. 11 09 647, the guide device consists of rigid rods, for example tension rods, on which the filter plates, fitted with sliders or rollers, directly rest. It is known in this connection to dispose these guide rods either in the vicinity of the lower filter plate corners or halfway up the height of the plates or in the vicinity of the upper filter plate corners. However, at these points, the guide rods frequently interfere with operation and the guides are also exposed to attack from the filter medium, which is disadvantageous especially in the case of corrosive filter media. In addition, the provision of sliders or rollers on the filter plates requires separate, relatively costly machining. In addition, there is frequently insufficient play provided to the filter plate package for a certain overall shape. Especially in the case of the filter plates which are increasingly in use today, often more than five square meters in size, which are assembled at very high pressures. As a result of irregularities in the filter plates spanned by filter cloth, forces build up which are directed toward an overall lifting of the filter plate package or a twisting of the filter plate package. In the case of rigid guides therefore, this can lead to destruction of the guides or to breakage of the filter plates.
The aim underlying the invention essentially resides in providing a filter press with a guide which ensures flush alignment of adjacent filter plates, with the guide being located outside the area affected by the filter medium, and being integrated in a space-saving manner in the filter press, while also allowing a certain twisting or other overall adjustment of the filter plate package.
On the basis of a filter press of the type described above, the solution to this problem is achieved according to the invention by virtue of the fact that the guide device is disposed on the filter plate suspension and include at least one guide rod running along the guide member and being elastically flexible to a limited degree, and each yoke piece is provided with at least one guide element fitting around the guide rod.
These measures result in the achievement of a number of advantages. For one thing a spatially compact arrangement of the filter plate suspension and guide is achieved so that the guides in no way still impede operation of the filter press, for example when changing the filter cloth. The guides are located a clear distance from the filter plates and thus outside the area of exposure to the filter medium, so that they remain protected against contamination and corrosive attack. Integrating the guide into the filter plate suspension eliminates the need for special machining on the filter plate. In addition, the guide permits certain intrinsic deformations of the entire filter plate package, but reliably ensures that adjacent filter plates remain aligned flush with one another when the filter press is closed in such fashion that the sealing edges of the filter plates always join one another to a sufficient degree to seal off the filter chambers.
A provision can be made in constructing the invention such that the guide rod is disposed immediately laterally next to one of the outside lower flanges of the guide rods. Alternatively however, according to the invention, provision can also be made such that the guide rod is disposed above the horizontal plane defined by the rollers, on the outside next to the guide members, and such that the yoke piece is provided with an arm which supports the guide element and fits around the lower flange of one of the guide members. In this manner, an increased distace between the filter plate suspension and the guide is achieved. The guide element can be disposed on the filter plate plane. An even greater distance between the filter plate suspension and the guide can be achieved in another embodiment of the invention by virtue of the fact that the guide element is disposed in a vertical plane which is staggered with respect to the plane of the filter plate.
According to the invention, one guide rod can be disposed on either side of the guide member and each yoke piece can have two guide elements which are staggered opposite to the staggering direction of the rollers relative to the filter plate plane. Each of the guide elements located next to one of the guide rods can lie in the same vertical plane as the roller guided on the other guide member. To produce the largest possible spacing relative to the central suspension, the guide rods can be disposed in the upper area of the guide members.
According to other features of the invention, provision can be made such that the guide elements are designed as pipe hangers or as a U-shaped part open at the top.
The guide rods according to the invention may include rods or tubes which are mounted on the support pillars opposite the end plate of the filter plate package and whose freely projecting ends pass through a guide holes in the end plates. Alternatively, the guide rods can consist of tensioned cables fastened to both supporting pillars and passing through a guide hole in the end plate.
The subject matter of the present invention will be described in greater detail below with reference to the accompanying drawings.